SID Which v0.92
(w) Professor Chaos, 2020

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INTRODUCTION
============

If you're reading this, you probably love Commodore 64 music. Hubbard.
Galway. But did you know that the SID sound chip was terribly inconsistent?
That on some machines, Hubbard's melodies are muffled? That you missed out
on either the beginning of Edwin van Santen's Spijkerhoek or the applause in
California Games? Or why Impossible Mission II sounds sometimes choppy and
sometimes full?

I wanted to know where these frail sections are and check what kind of SID
they sound best on. Initially, I searched for these sections using the Graph
on http://deepsid.com and SIDDump from https://cadaver.github.io
Excellent tools, but cumbersome for my purpose.

Thus, SID Which was born. It highlights the frail sections of every SID song
to you. You then open your favorite C64 emulator or SID player (like VICE or
XMPlay) and listen to these sections, while adjusting the SID model (6581 or
8580, criteria see below) and filter bias/strength until all sounds cool.

Please note that it will not give you "final answers". I'm not even sure if
this is possible. But it should lead you the right way.

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INSTALLING
==========

Before opening SID files, you must download
  https://hvsc.de/download/C64Music/DOCUMENTS/Songlengths.md5
and drag and drop it into one of the two "SID Which" windows, or click the
"Songlengths database" button on the top left. The filename should
instantly appear next to the button.

If you also have an interest in sound drivers, download
  https://raw.githubusercontent.com/cadaver/sidid/master/sidid.cfg
and, again, either drag'n'drop or click "Driver database (SIDID)".

Done!

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TABLE
=====

To examine SID files, drag and drop them into one of the two "SID Which"
windows, press the INSERT key, or click the "Add" button.

        File: The whole path to the rip and the subtune number in
              parentheses (unless only one subtune in the rip). Every time
              you select a subtune (by click or arrow key), the graphs start
              displaying it. Double-click and the RETURN key do the same as
              in Explorer, i.e. if you have associated SID files with a
              player, that player will start.

         $51: "?" if the subtune has not finished yet.
              "X" if the subtune uses the combined triangle and pulse wave.
                  In the graph, it's yellow.
                  On the 6581, it sounds thinner.
                  On the 8580, it sounds fuller.

         $61: "?" if the subtune has not finished yet.
              "X" if the subtune uses the combined sawtooth and pulse wave.
                  In the graph, it's purple.
                  On the 6581, it is often mute, and if it isn't, it sounds
                  an octave higher (which only VICE 3.4 emulates correctly).
                  On the 8580, it sounds fine.

         $31: "?" if the subtune has not finished yet.
              "X" if the subtune uses the combined triangle, sawtooth and
                  maybe also pulse wave (then actually $71, not just $31).
                  In the graph, $31 is yellow and $71 is light gray.
                  On the 6581, they are very quiet, although it may fit with
                  apparent lullabies like /GAMES/A-F/Fire_Bug.sid

      Filter: "?" if the subtune has not finished yet.
              "L" if the subtune uses a low-pass filter (gray in graph).
              "B" if the subtune uses a band-pass filter (white in grpah).
              "H" if the subtune uses a high-pass filter (brown in graph).
              All passes can be combined. The 6581 filter is infamous for
              sounding different on every single machine, sometimes muting,
              muffling or unbearably sticking out sounds. The 8580 filter is
              consistent, but can produce sounds which the 6581 couldn't.

       Digis: Empty if the subtune does not use samples at all.
              "?" if the subtune MIGHT use 4-bit PCM samples. At the moment,
                  the only way to see it REALLY does, is to select the tune
                  and look at the bottom graph. If you see thick bars (like
                  in, say, Audacity), it uses 4-bit PCM samples.
                  On the 6581, they are loud.
                  On the 8580, they are quiet, sometimes even mute.

        Warn: Empty if nothing wrong has been found with this subtune.
              "?" if you should double-check the subtune. At the moment, a
                  few songs don't actually play, which usually shows in the
                  volume staying at 0 or graphs suddenly stopping to change.
              "!" if the song breaks at some point (at which the graphs'
                  backgrounds became red). Sometimes it's a bug in the rip,
                  sometimes it's a bug in SID Which.
              On the top of c64.c I've noted the rips where SID Which has a
              bug.

    Duration: The number of seconds (or rarely, milliseconds) the subtune
              lasts. Requires the above "Songlengths database", otherwise
              this and 4 other columns will be wrong.

       Title: The title of all subtunes or its game. Titles of individual
              subtunes may be found in STIL.txt, next to "NAME:".

   Artist(s): All arrangers attributed to all subtunes in the rip. Arrangers
              of individual subtunes may be found in STIL.txt, next to
              "AUTHOR:". If they end with "<?>", they are not actually
              confirmed, only guessed.

   Driver(s): All drivers found in the rip. Requires the above "Driver
              database (SIDID)". Drivers only found in ONE rip are not in
              the database.

        Year: When the subtunes in the rip were released. Ranges (like
              "1985-86") stand for guesses, not multiple releases. Songs
              from 1985 or earlier are for 6581 (the 8580 didn't exist yet).

Publisher(s): All publishers attributed to all subtunes in the rip. Some
              rips also list the developer here.

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LICENSE
=======

Copyright 2020 Sebastian Sprenger. Based on SIDDump V1.08 Copyright (C)
2005-2020 by the authors. All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:

1. Redistributions of source code must retain the above copyright notice,
this list of conditions and the following disclaimer.

2. Redistributions in binary form must reproduce the above copyright notice,
this list of conditions and the following disclaimer in the documentation
and/or other materials provided with the distribution.

3. Neither the name of the copyright holder nor the names of its
contributors may be used to endorse or promote products derived from this
software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
POSSIBILITY OF SUCH DAMAGE.